The anatomical organization of the limbic system with special emphasis on the vomeronasal system is being studied by the use of experimental degeneration techniques, autoradiographic tracing of axoplasmic flow and horseradish peroxidase intra-axonal transport. The snake is presented as an ideal experimental subject for these studies because of its exceptionally well developed vomeronasal system, the large proportion of its telencephalon devoted to limbic system structures and the relative absence of a developed neocortex. Our goal is to develop a working model of limbic system organization in a relatively simple nervous system. This model will then be available for use in interpreting our own behavioral experiments on the role of the vomeronasal system in trailing behavior. A relatively simple model of limbic system organization would also be usable as a basis for understanding the limbic system of more complex vertebrates.